There is a paucity of information about tobacco-related morbidity and mortality in patients with other addictive disorders. This study will answer the question of whether there is excessive tobacco-related disease in patients undergoing treatment for other addictive disorders and will help define the burden of untreated nicotine dependence in these patients. Our specific aims are as follows: * To estimate excess, cause-specific disease incidence and mortality rates in the cohort of Olmsted County, Minnesota patients admitted to the Alcoholism and Drug Dependence Unit in 1974-83 and followed through 1991, as compared to expected rates for the general county population. * To compare the disease incidence and mortality experience of smoking and nonsmoking patients in the cohort in order to test the hypothesis that some of the excess is associated with continued smoking. Using the Rochester Epidemiology Project medical records linkage system, the study will provide population-based information about the risk of tobacco-related illnesses among Olmsted County, Minnesota residents treated in the Alcoholism and Drug Dependence Unit of Mayo Clinic from 1974 through 1983 (n=817). This system provides efficient access to all clinical data for Olmsted County residents and is one of the few settings where the proposed study can be accomplished. The complete (inpatient and outpatient) medical records of each patient will be abstracted. The patients will be followed forward from the time of admission to the ADDU using the linked medical records until death, emigration, or the present. Preliminary data show a high frequency of tobacco-related diseases in the cohort and that there was a higher than expected number of deaths. This indicates the large number of events that will be available for analysis.